1. Field of the Invention
This invention generally relates to beverage brewers, and methods of brewing and, more particularly, to beverage brewers and methods of brewing in which the quantity of brewing liquid that is delivered to the brewing ingredient and the time period during which the brewing liquid is dispensed into a brewing ingredient holder is automatically controlled, and to beverage ingredient filters in which the ingredient is contained during brewing.
2. Discussion of the Relevant Prior Art
The inventor has determined that there is a common problem associated with all commercial beverage brewers of the drip-type in which the brew liquid is passed through brewing ingredient. The brewing ingredient is ground coffee, ground tea, tea leaves and other like dry beverage ingredients. The beverage brewing liquid is generally plain hot water The brew ingredients have a residue or structure that contains the essential dry beverage components. When the beverage brewing liquid that is passed through a layer of the dry beverage ingredient during the dispensing period of the brewing cycle and the post-dispense drip period, the dry beverage ingredients are dissolved and released into the beverage brewing liquid upon contact. The brewing ingredient is generally contained within a removable filter that is supported within a brew basket that is movably mounted beneath a brewing liquid dispenser, or dispenser, to receive the hot brewing water. The filter is manually loaded with beverage ingredient and then placed in a filter holder within the brew basket. Each of the brew basket and the filter holder has a generally truncated conical shape with sides that slope inwardly from the open top of the brew basket to the beverage dispenser outlet that is located at the bottom of the brew basket.
The problem with this arrangement is that it is not possible to obtain a uniform contact of the hot brewing water with the ingredient within the brew basket during the dispensing period while the hot water is being dispensed and the subsequent post-dispensing drip period of the brew cycle. In the case of ground coffee, when hot water first makes contact with the coffee gases are generated that causes the coffee grounds to foam upwardly and also to float layers of hot water that have not yet seeped through the upper surface of the layer of hot coffee.
The inventor believes that for this reason and because of the generally conical shape of the layer of beverage ingredient, and despite continuous spraying of the hot brewing water across the upper surface of the beverage ingredient, some of the ingredient, generally nearer the side walls of the brew basket, does not receive sufficient contact with the hot water to strip off all the beverage ingredient component to be dissolved into the water that is being held by the beverage ingredient. The beverage ingredient is therefore wasted. Likewise, other portions of the beverage ingredient, generally closer to the central portion of the brew basket receive too much contact with the hot water, ie. more contact with the water than needed to dissolve all the beverage ingredient components, and other undesirable ingredient components are dissolved into the brewed beverage. Consequently, optimum brewing of the beverage ingredient is not obtained and the brewing ingredient component that does not dissolve into the hot water because of insufficient hot water contact with the associated brewing ingredient is wasted.
Both the time of contact of the hot water with the beverage ingredient and the amount of hot water that is mixed with a given amount of beverage are critical to optimizing the quality of the resulting brewed beverage. Different types of beverage ingredient, such as different types of coffee, and different forms of a given beverage ingredient, such as a given ground coffee of different degrees of coarseness require different amounts of hot water for optimum brewing of the resulting beverage. Unfortunately, there is another problem of known beverage brewers which exacerbates the nonuniform ingredient saturation problem noted above. The problem is the inability to easily adjust the quantity of hot water that is dispensed without changing the duration of the dispensing time period, and the inability to easily adjust the duration of the dispense period without changing the quantity of hot water that is to be dispensed.
The truncated conical shape of know beverage ingredient filters precludes them from being easily stacked or packaged and accordingly in all known commercial drip-type brewers the conical filters are manually loaded with ingredient at the coffee brewing site.
Reference should be made to U.S. Pat. No. 5,000,082 entitled xe2x80x9cBeverage Maker And Method Of Making Beveragexe2x80x9d issued Mar. 19, 1991 and U.S. Pat. No. 5,331,885 entitled xe2x80x9cSemiautomatic Beverage Maker And Methodxe2x80x9d issued Jul. 26,1994 of the present inventor and the patents cited therein, all of which are incorporated herein by reference, for structural, mechanical and other details of the conventional components of coffee brewers and the like, with reference to the features noted above, and in general with reference to the embodiments described below to the extent conventional elements are disclosed in functional block form only and such details are desired.
In U.S. Pat. No. 5,375,508 issued to Knepler et al ofn Dec. 27, 1994 for a xe2x80x9cDigital Brewer Controlxe2x80x9d mechanisms are shown that enable intermittent dispensing of the hot water into the brew basket. However, this is done solely to slow down the average rate of dispensing, or infusion, of the water into the brew basket to prevent overflowing the brew basket. Such overflowing occurs during continuous dispensing under the special circumstances of decaffeinated coffee and soft water that reduces the rate of outflow from the brew basket. However, there is nothing to suggest using such intermittent flow for purposes of obtaining uniform extraction when dealing with different amounts or different types of coffee.
Accordingly, it is the primary object of the present invention to provide a beverage brewer and a method of brewing in which the aforementioned problems of known beverage brewers and brewing methods are overcome.
This objective is achieved in part by providing a beverage brewer with a beverage ingredient holder; and a dispenser assembly with means for automatically, intermittently, delivering brewing liquid into the beverage ingredient holder during a dispensing period of a brewing cycle. Preferably the dispenser assembly includes a dispenser valve, and a dispenser valve controller to control the valve for automatically, intermittently, delivering the brewing liquid into the beverage ingredient holder during the dispensing period of the brewing cycle.
Preferably, the dispenser valve controller includes means for dividing the dispensing period into a plurality of dispensing control periods, means for establishing a duty portion for at least some of the plurality of dispensing control periods, and means for actuating the dispensing valve to pass the brewing liquid to the beverage ingredient holder only during the preselected duty portion of each of the plurality of dispensing control periods.
The duty portion establishing means includes means for selectively controlling the duration of the duty portion the plurality of dispensing control periods. Different duty portions for different dispensing control periods of the same dispensing period are established to selectively vary the average flow rate at different segments of the dispensing period. The duty portion controlling means includes means for increasing the duty portion of each successive dispensing control period occurring during the dispensing period. The duty portion controlling means also preferably includes means for decreasing the duty period of each successive dispensing control period occurring during the dispensing period. Preferably, the dispenser assembly includes a computer that is programmed to control intermittent delivery of the brewing liquid to the beverage ingredient holder.
In keeping with another aspect of the present invention, the beverage ingredient holder has a brewing liquid receiving opening, and the dispenser includes a dispenser head assembly with a field of substantially uniformly spaced apart dispensing holes of substantially the same size located in coextensive overlying relationship with respect to the brewing liquid receiving inlet opening of the beverage ingredient holder and the beverage ingredient holder has a portion for supporting all of the ingredient in a substantially straight tubular configuration with spaced parallel upper and lower surfaces substantially entirely overlain by the field of dispensing holes. Preferably, the ingredient support surface is circular and the straight tubular configuration of the ingredient portion of the beverage ingredient holder is substantially cylindrical.
In accordance with another feature of the beverage brewer of the invention, the beverage brewer has a dispenser head assembly with a substantially closed body with a field of dispenser holes defining a bottom of the body and a top wall spaced oppositely from the field of dispenser holes supporting a brewing liquid inlet. A stream deflector is mounted in a blocking position between the brewing liquid inlet and the field of dispenser holes to reduce any uneven pressurization of the field of holes. A dispenser valve is periodically opened to intermittently fill the dispenser head body with brewing liquid and to uniformly force the brewing liquid out of all the dispenser holes under a uniform pressure.
Another advantageous feature of the invention is that the dispenser valve controller includes means for preselecting a length of time for the dispensing period, and means for selectively varying the total amount of brewing liquid delivered to the ingredient holder during the dispensing period of preselected length by varying the duration the intermittent periods of delivery during the dispensing period of the brewing cycle. Preferably, the intermittently delivering means includes means for dividing the dispensing period into a plurality of control periods each having a duration on the order of fifteen-seconds, and means for delivering brewing liquid during a portion of each of the control periods during the dispensing cycle. Preferably, the valve controller is a computer.
In accordance with another aspect of the invention, a beverage ingredient assembly is provided having a tubular mass of beverage ingredient configured into a tube having parallel side walls joined at opposite ends to a continuous planer top and a continuous planer bottom that are parallel to each other and substantially perpendicular to and continuously spanning the parallel side walls and a disposable water and beverage permeable filter envelope snugly enclosing the tubular mass. Preferably, the tubular mass is configured as a solid cylinder, and the permeable filter envelope is made of filter paper. The proper tubular shape of the beverage ingredient is thereby maintained while the loading of the filters is capable of being performed on an automated basis and then the beverage ingredient assemblies packaged in a vacuum container in a stacked relationship which is not easily done with truncated conical shapes of the known brewers.
In accordance with one aspect of the brewing method of the present invention independent control of the dispense period and the total brewing liquid dispensed by preselecting a dispense time period of a brewing cycle during which brewing liquid is dispensed onto a top of a beverage ingredient layer and automatically selecting a number of control periods during which beverage liquid is capable of being dispensed onto a top surface of the beverage ingredient layer in accordance with the dispense time period that has been selected and dispensing the brewing liquid onto the top surface during at least some of the number of control periods that have been selected. The duty portion of at least some of the control periods during which the brewing liquid is dispensed onto the top of the beverage ingredient layer is changed in indirect relationship to any change in the number of control periods selected to substantially fix a preselected total amount of brewing liquid dispensed during different preselected dispense time periods.
Likewise, the method includes the steps o preselecting a total amount to be dispensed during a dispense period composed of a plurality of control periods of a brewing cycle during which brewing liquid is capable of being dispensed onto a top of a beverage ingredient layer, automatically selecting a duty portion of at least some of the plurality of control periods during which the brewing liquid is capable of being dispensed onto a top surface of the beverage ingredient layer of at least some of the control periods in accordance with the total amount to be dispensed that has been preselected, and dispensing the brewing liquid onto the top surface during the duty portions of the control periods that have been selected. The duty portion of at least some of the control periods during which the brewing liquid is dispensed onto the top of the beverage ingredient layer is directly controlled in indirect relationship to any change in the number of control periods selected to substantially maintain the preselected total amount of brewing liquid to be dispensed.